The Solid OIDC Access Token Verifier is a JavaScript library that verifies Solid OIDC access tokens using their `webid` claim to assert ownership of a WebID. It supports both DPoP Bound and Bearer Access Tokens, includes caching mechanisms for identity providers and JSON Web Key Sets, and provides a simple function for token verification. This tool is designed for developers building Solid applications who need to authenticate users via Solid's decentralized identity system.